The Mormons have added The Book of Mormon, The Pearl of Great Price, and Doctrine and Covenants as the source of their "church" doctrine. These books teach:
* God was not always God but was once a man. (Teachings of the Prophet Joseph Smith, pg. 345)
* Jesus and Satan are brothers. (Gospel Through the Ages, pg. 15)
* Adam was God. (Journal of Discourses 1:50; 4:1)
* Jesus was a polygamist. (Journal of Discourses 2:210)
* Brigham Young said only polygamists become gods. (Journal of Discourses 11:269)
* The Bible cannot be trusted according to Joseph Smith. (Teachings of the Prophet Joseph Smith, pg. 327)
* Almost every verse of the Bible has been corrupted. (The Seer, pg. 213)
* You must believe that Joseph Smith is a prophet to be saved. (Doctrines of Salvation, no page given)
My source for this information is: http://www.nowtheendbegins.com/pages/cults/church-of-mormon-latter-day-saints.htm
Mormonism is so dangerous to those who have little Bible knowledge, in that, it uses biblical terms, which to the Mormons, mean something totally different that is found in the Bible.
The best defense against false doctrine is to know the truth; the Bible is truth!